The present invention relates to an automatic performance apparatus for an electronic musical instrument, which can alter a performance pattern in an automatic performance in accordance with the instruction by a player.
Recent electronic musical instruments, such as an electronic keyboard, electronic organ and electronic piano and the like, are equipped with an automatic performance apparatus which executes an automatic performance like an automatic rhythm accompaniment or automatic chord accompaniment. The use of this automatic performance apparatus permits a player to play melodies or the like in accordance with an accompaniment that is automatically produced by the automatic performance apparatus.
This automatic performance apparatus repeatedly reads out automatic performance data corresponding to a selected performance pattern from a memory and supplies the data to a tone generator. The tone generator generates a tone signal based on this automatic performance data and sends the tone signal to a loudspeaker. The loudspeaker then generates an accompaniment accordingly.
The automatic performance apparatus has a function to change a performance pattern at the beginning, ending or middle of music, besides the above mentioned function of generating an accompaniment which is formed by repeating a given performance pattern. The former function helps presenting a varied automatic performance so that a modulated accompaniment can be produced.
To accomplish the performance-pattern altering function, the automatic performance apparatus has a memory where one to several bars of automatic performance data corresponding to each of the performance patterns namely "introduction" (hereinafter called "intro"), "basic", "fill-in" and "ending", are stored. The automatic performance data is of the same format as the one used in an embodiment of the present invention and is exemplified in FIG. 3. The details will be given later.
The player selects "intro", "basic" "fill-in" or "ending" using an operating element provided on, for example, a control panel. Through this selection, the electronic musical instrument can perform an automatic accompaniment with the desired performance pattern.
"Basic" is a basic performance pattern of rhythms. Normally, when a automatic performance start switch provided on, for example, the control panel is depressed, an automatic accompaniment with this basic performance pattern (hereinafter called "basic performance") starts. This basic performance continues until an ending switch, which will be discussed later, is depressed.
"Intro" is a performance pattern which is used to execute an automatic performance having a predetermined characteristic before the basic performance. When an intro switch provided on, for example, the control panel, is depressed, an automatic performance with this "intro" performance pattern (hereinafter called "intro performance") is executed for a given number of bars (e.g., one bar), after which the basic performance takes place.
"Ending" is a performance pattern which is used to execute an automatic performance having a predetermined characteristic to end the basic performance. When the ending switch, provided on, for example, the control panel, is depressed during the basic performance, the basic performance stops and an automatic performance with this ending performance pattern (hereinafter called "ending performance") is executed for a given number of bars (e.g., one bar), after which the automatic performance is terminated.
"Fill-in" is a performance pattern which is used to execute an automatic performance having a predetermined characteristic during the basic performance. When a fill-in switch provided on, for example, the control panel, is depressed during the basic performance, the basic performance which has been performed at that point is temporarily interrupted, and a fill-in performance is executed for a given number of bars (e.g., one bar), after which the basic performance is resumed. This fill-in is used to modulate an automatic performance.
An automatic performance apparatus having performance patterns for two types of "basics " having the same rhythm (hereinafter called "basic 1" and "basic 2") has also been developed recently. The performance pattern of basic 1 is used for the normal automatic performance, for example. The performance pattern of basic 2 is used for a loud automatic performance containing a variety of high-volume timbres, such as the one that is played at the climax (hereinafter called "automatic performance for climax").
According to this automatic performance apparatus, when, for example, a variation switch provided on the control panel is operated, an automatic performance with the performance pattern of basic 1 (hereinafter called "basic 1 performance") during an automatic performance is changed to an automatic performance with the performance pattern of basic 2 (hereinafter called "basic 2 performance"), or vice versa. The player can therefore accomplish the transition from the normal automatic performance with the performance pattern of basic 1 to the automatic performance for climax of the same rhythm with the performance pattern of basic 2, or vice versa by operating the variation switch as needed.
This automatic performance apparatus however has a shortcoming that when the variation switch is operated, the basic 1 performance is changed to the basic 2 performance or vice versa abruptly, so that the transition is not aurally smooth, causing the player to feel awkward. With the conventional automatic performance apparatuses, therefore, it is difficult to gradually reach the climax as music progresses. Further, many control switches are needed for controlling each automatic performance of intro, basic, fill-in and ending. Therefore, an automatic performance apparatus provided with fewer control switches is required.